Robot system having function of simplifying teaching operation and improving operating performance by learning

Abstract

A robot system includes a detector for detecting the position and posture of a workpiece; a robot for performing a predetermined operation on the workpiece; and a robot control device. The robot control device includes an area divider for dividing an operation area into a plurality of areas; an area determiner for determining in which area the workpiece is present; a learning controller for learning an operation speedup ratio to speed up an operation by varying speed or acceleration on an area-by-area basis in which the workpiece is present; a memory for storing the position of the workpiece and the operation speedup ratio; and a controller that performs the operation on a new workpiece using the learned operation speedup ratio when the operation has been learned in the area having the new workpiece, and makes the learning controller learn the operation speedup ratio when the operation has not been learned.

What is claimed is: 
     
       1. A robot system, comprising:
 a detector for detecting the position and posture of a workpiece to be operated present in a predetermined operation area; 
 a robot for performing a predetermined operation on the workpiece based on information about the detected position and posture; and 
 a robot control device for controlling the robot, 
 wherein the robot control device includes:
 an area divider for dividing the operation area into a plurality of areas of a predetermined size; 
 an area determiner for determining in which area of the plurality of areas the workpiece is present; 
 a learning controller for learning an operation speedup ratio to speed up the operation by varying speed or acceleration on an area-by-area basis for the plurality of areas; 
 a memory for storing the position and the operation speedup ratio of the area, among the plurality of areas, in which the workpiece is present; and 
 a controller for determining whether or not the operation has already been learned in an area, among the plurality of areas, in which a new workpiece is present, and when the operation has already been learned, the controller controls the robot to perform the operation on the new workpiece using the learned operation speedup ratio, and when the operation has not been learned, the controller makes the learning controller learn the operation speedup ratio, and 
 
 wherein the learning controller changes a priority of operation of each of the plurality of areas in accordance with a state of learning. 
 
     
     
       2. The robot system according to  claim 1 , wherein the operation includes a grasping operation by which the robot grasps the workpiece disposed in the operation area and a putting operation in which the robot puts the grasped workpiece in a workpiece completion area. 
     
     
       3. The robot system according to  claim 1 , wherein
 the learning controller calculates the operation speedup ratio based on an allowable load of a motor for driving each axis of the robot and a load of the motor during execution of an operation pattern, and 
 the memory stores the operation speedup ratio together with operation information,
 the operation information including at least one of the speed and the acceleration before learning the operation. 
 
 
     
     
       4. The robot system according to  claim 3 , wherein
 before execution of the operation, the learning controller retrieves a learned operation that is similar to the operation, 
 when the learned operation is present, the operation speedup ratio is corrected by the learning controller based on
 an operation speedup ratio associated with the learned operation, and 
 a difference between information on the operation before execution and information on the learned operation, and 
 
 the controller speeds up the operation using the corrected operation speedup ratio. 
 
     
     
       5. The robot system according to  claim 1 , wherein
 the learning controller calculates the operation speedup ratio based on difference information between a command value to a motor for driving each axis of the robot and a feedback value from the motor during execution of an operation pattern, and 
 the memory stores the operation speedup ratio together with operation information,
 the operation information including at least one of the speed and the acceleration before learning the operation.